| name | pain-assessment |
| description | Glasgow Composite Pain Scale (dogs), FMPI/UNESP-Botucatu (cats), Colorado State pain scales, multimodal analgesia ladder, species-specific pain indicators, opioid/NSAID protocols with dosing. |
Pain Assessment
Overview
Validated, species-specific pain assessment tools with interpretation guidance. Includes acute and chronic pain scales, multimodal analgesic protocols, and species-specific pain manifestations (especially feline pain hiding).
When to Use
- User performs perioperative/acute pain assessment or pain management planning
- User needs pain scale interpretation or analgesic selection/dosing
- Keywords: pain, analgesia, Glasgow, UNESP, FMPI, pain scale, acute pain, chronic pain, multimodal, opioid, NSAID, gabapentin, meloxicam, tramadol
Glasgow Composite Pain Scale (GCPS) - Dogs
Scoring: Observer-rated scale; 0-26 points (higher = more pain); sections for behavior, posture, consciousness, physiologic values
| Domain | 0 Points | 1 Point | 2 Points | 3+ Points |
|---|
| Vocalization | Silent | Crying/groaning | Howling | Constant vocalization |
| Body Tension | Relaxed | Slightly tense | Moderate tension | Rigid/severe tension |
| Posture | Normal | Slightly abnormal | Moderately abnormal | Severely abnormal (hunched, stretched) |
| Consciousness | Normal | Drowsy | Depressed | Unresponsive |
| Appetite | Eating normally | Reduced intake | Not eating | Vomiting/retching |
| Responsiveness | Normal behavior | Slightly subdued | Withdrawn | Unresponsive/hostile |
Interpretation: 0-4 = minimal pain; 5-13 = mild-moderate pain; 14-26 = severe pain
Trending: More important than absolute score; assess pre-treatment and post-analgesic to evaluate efficacy
Feline Musculoskeletal Pain Index (FMPI) and UNESP-Botucatu
FMPI (6 items scored 0-3): Lameness, reluctance to move, pain on palpation, posture abnormalities, activity level, dynamic gait changes
- Interpretation: 0-3 = minimal, 4-9 = mild-moderate, 10-18 = severe pain
- Critical: Cats hide pain; absence of vocalization does NOT indicate absence of pain
FMPI Behavioral Indicators of Pain:
- Reduced activity, reluctance to jump
- Abnormal gait or position changes
- Reduced grooming/self-care
- Behavioral changes (aggression, withdrawal)
- Palpable muscle rigidity, guarding
UNESP-Botucatu (Alternative feline scale): Behavioral components (posture, activity, lameness) + physiologic (appetite, autonomic signs); used primarily in research settings
Colorado State Pain Scale (Multi-Species)
Acute Pain Categories:
- Pain Behaviors: Vocalization, posture abnormality, aggression, self-mutilation, attention to wound
- Physiologic Signs: Tachycardia, tachypnea, hypertension, mydriasis, salivation/lacrimation
- Wound/Disease Assessment: Swelling, discharge, redness, lameness severity
Chronic Pain: Similar assessment but includes behavioral/activity changes (depression, reduced movement, sleep disturbance)
Multimodal Analgesia Ladder
Tier 1: Non-Pharmacologic
- Physical: Rest, ice/heat application, physical therapy, passive range of motion
- Environmental: Quiet recovery space, soft bedding, frequent positioning
Tier 2: Oral/Injectable Analgesics (Acute)
NSAIDs (first-line for inflammatory pain):
- Dogs: Meloxicam 0.1-0.2 mg/kg daily; carprofen 4.4 mg/kg/day (2.2 mg/kg BID or 4.4 mg/kg SID — do not exceed); deracoxib 1-2 mg/kg daily; firocoxib 5 mg/kg daily (canine dose)
- Cats: Meloxicam — ⚠️ FDA black-box warning; US label is a single one-time 0.3 mg/kg SC dose. If chronic use is justified, ~0.05 mg/kg once daily (lowest effective) with mandatory renal monitoring (see
safety/nsaid-safety). Do not give repeated 0.1 mg/kg daily as routine.
- Dosing caveat: NSAIDs contraindicated in dehydration, renal disease, hepatic disease, GI ulceration; monitor PCV/TP, creatinine, BUN
Opioids (acute severe pain):
- Dogs (acute): Morphine 0.5-1 mg/kg IM/SC q4-6h; hydromorphone 0.05-0.1 mg/kg IM/SC q4-6h; buprenorphine 0.01-0.02 mg/kg IM/IV q6-12h
- Cats (acute): use lower opioid doses — morphine 0.1-0.3 mg/kg IM/SC (higher doses risk excitation/hyperthermia); hydromorphone 0.05-0.1 mg/kg; buprenorphine 0.01-0.02 mg/kg (transmucosal effective)
- Dogs (chronic): Tramadol 5-10 mg/kg TID-QID; lower efficacy than traditional opioids; less abuse potential
- Cats (chronic): Buprenorphine preferred (longer duration, less hyperthermia risk); 0.01-0.02 mg/kg q6-12h (transmucosal absorption)
Tier 3: Adjuvant Agents
- Gabapentin (neuropathic/chronic pain): Dogs 10-20 mg/kg TID; Cats ~10 mg/kg (start 5-10, up to ~20; ≈50-100 mg/cat) BID-TID — 100-200 mg is high for a typical 4-5 kg cat, so start low; slower onset (days-weeks) but excellent for chronic neuropathic pain
- Amantadine (NMDA antagonist): 3-5 mg/kg daily-BID; useful for chronic pain and opioid tolerance
- Alpha-2 agonists (acute): Dexmedetomidine 5-10 mcg/kg IM/IV (profound sedation; reversal with atipamezole); not recommended for prolonged pain management
- Corticosteroids (inflammatory pain, limited duration): Prednisolone 0.5-1 mg/kg initial; taper after acute phase to avoid complications
Tier 4: Regional/Interventional
- Local anesthetic blocks: Ring blocks (digit), maxillary/mandibular blocks, intra-articular injections
- Epidural anesthesia: Morphine 0.1 mg/kg + local anesthetic; prolonged postoperative analgesia
- Joint injections: Steroid (triamcinolone, dexamethasone) ± local anesthetic for chronic OA
Species-Specific Pain Indicators
Dogs
- Vocalization (whining, whimpering, howling)
- Posture changes (hunched, stretched, shifting weight)
- Appetite suppression
- Activity reduction
- Licking/biting at wound or affected area
- Reluctance to stand/move
Cats
- UNDERREPORT pain behaviors; quiet cats often in significant pain
- Reduced grooming (hunched, unkempt appearance)
- Reluctance to move/jump
- Hidden behavior (seeking quiet, dark spaces)
- Subtle aggression, irritability
- Loss of appetite (early indicator)
- Altered sleep patterns (restlessness)
Critical: Absence of vocalization in cats does NOT = absence of pain; behavioral and gait assessment essential
Small Mammals/Exotics
- Rabbits: Teeth grinding (bruxism), eye bulging (pain squeeze), immobility, reduced eating, hunched posture
- Rodents: Reduced activity, porphyrin around eyes (stress), piloerection, huddle posture
- Birds: Ruffled feathers, reluctance to move, wing drooping, lack of preening
Perioperative Analgesic Protocol Example (Dog, Soft Tissue Surgery)
- Pre-emptive: Meloxicam 0.2 mg/kg PO/IV (1 hour pre-op)
- Intra-operative: Morphine 0.5 mg/kg IM (30 min pre-op); local anesthetic ring block or incision-line infiltration
- Immediate recovery: Meloxicam q24h × 5-7 days; morphine IM/SC q4-6h PRN first 24-48 hours (assess GCPS)
- Home care: Meloxicam daily × 7-10 days; oral gabapentin 15 mg/kg TID if high-anxiety patient or chronic pain risk
Opioid/NSAID Considerations
Concurrent Use: NSAIDs + opioids acceptable (multimodal); reduces required opioid dose, lowers GI ulceration risk
Corticosteroid Washout: Avoid NSAIDs <1 week after systemic corticosteroid discontinuation (ulceration risk)
Renal Monitoring: Baseline + 7-14 days into NSAID therapy (assess creatinine, BUN, urine specific gravity); especially critical in geriatric patients, dehydrated animals, or those with pre-existing renal disease
Hepatic Monitoring: Baseline liver enzymes if prolonged NSAID use (>2 weeks) in at-risk patients
Key Species Differences
- Dogs: Tolerate NSAIDs well; opioid tolerance develops over weeks; gabapentin effective for chronic neuropathic pain
- Cats: Meloxicam dosing controversial/contentious (use judiciously); excellent responders to gabapentin; buprenorphine preferred opioid (higher partial agonist ceiling effect); pain behaviors subtle
- Rabbits/Rodents: High metabolic rate; shorter analgesic intervals; tramadol less effective; opioids prone to GI stasis (combine with motility agents)
- Exotics: Species-specific pharmacokinetics vary widely; consult specialized resources before prescribing
Limitations
- Pain scales: Observer-dependent subjective assessment; provide framework only, not absolute diagnosis
- Feline pain assessment: Cats significantly undertreat due to cryptic pain behaviors; provider awareness essential
- NSAID safety: Contraindications common (renal disease, GI ulceration, dehydration); not universal analgesic choice
- Opioid tolerance: Develops within days-weeks; rotation or adjuvant strategies needed for chronic pain
- Regional anesthesia: Requires technical skill; duration limited (4-24 hours depending on agent)
- Chronic pain: Long-term analgesic strategies less evidence-based than acute protocols; referral to pain specialist recommended for refractory cases
